That's a Win-specific error.
    When we create libmysqld.dll we have many libraries like mysys, dbug,
    strings, etc linked into that dll, so the application built upon
    this library shouldn't link these libraries to itself, rather use
    those inside the dll.

    Fixed by redirecting calls into the libmysqld.dll

per-file comments:
  dbug/dbug.c
Bug#38293 Libmysqld crash in mysql_library_init if language file missing
    fake _db_something definitions added

  include/my_dbug.h
Bug#38293 Libmysqld crash in mysql_library_init if language file missing
  fake _db_something declarations added

  libmysqld/examples/CMakeLists.txt
Bug#38293 Libmysqld crash in mysql_library_init if language file missing
    superfluous libraries removed from linking

  libmysqld/libmysqld.def
Bug#38293 Libmysqld crash in mysql_library_init if language file missing
    set of mysys functions added to the export section